An excerpt published in Vanity Fair from the book The Crimes of Paris: A True Story of Murder, Theft, and Detection, by Dorothy and Thomas Hoobler:

As the Louvre’s maintenance director, a man named Picquet, passed through the Salon Carré during his rounds on the morning of August 21, 1911, he pointed out Leonardo’s Mona Lisa, telling a co-worker that it was the most valuable object in the museum. “They say it is worth a million and a half,” Picquet remarked, glancing at his watch as he left the room. The time was 7:20 a.m.

Shortly after Picquet departed the Salon Carré, a door to a storage closet opened and at least one man—for it would never be proved whether the thief worked alone—emerged. He had been in there since the previous day—Sunday, the museum’s busiest. Just before closing time, the thief had slipped inside the little closet so that he could emerge in the morning without the need to identify himself to a guard at the entrance.

After visiting the Louvre in Paris, I was curious about the security measures employed to protect the Mona Lisa. Little did I know that it had already been stolen once before, in 1911. This story of the theft and subsequent recovery is riveting.